Method of producing an optically effective arrangement, in particular for application with a vehicular headlight

ABSTRACT

A vehicular headlight, in particular an automobile headlight, including a reflector (1) having a reflecting surface, is capable of illuminating a flat target surface to be illuminated with a desired light distribution by optimal utilization of the light source of the headlight. Therefore the optically effective surface of the headlight is characterized by point asymmetry in substantially all planes cutting said reflecting surface. This can be realized by using a method for producing said optical surface comprising the steps of: mathematically representing said surface by creating a spline from bivariate tensor product of polynomials; deriving mathematical data in computer input format from said mathematical representation; and inputting said data to a computer for controlling an apparatus by which the mathematical representation of said optical surface is reproduced in physical form. Such splines, in turn, are represented and subsequently altered, preferably either by the so-called Bezier method or by the so-called Basis-spline method.

The invention relates to a method for producing an optically effective arrangement comprising one reflective surface, said arrangement having a light source related to an optical axis which extends in alignment with the optical arrangement for distributing light of said light source reflected by said reflective surface according to a desired light pattern, in particular for application with a vehicular headlight.

Due to legal regulations directed to traffic safety, some known automobile headlights are provided with a masking element arranged in the beam of light between the reflector and a distributor lens in order to meet specific requirements with respect to illumination range, color uniformity, the illumination pattern on the roadway and its marginal area, and light/dark delimitation criteria.

The use of such masking elements, however, is one of the main reasons why such headlights mentioned can neither produce their full light output, nor are they free from the occurrence of color fringes, which runs counter to the requirement for emitting a uniformly colored light.

An automobile headlight is known from DE-AS 18 02 113 by means of which a sharp light/dark delimitation (low beam headlights) is to be achieved without the use of a masking element. For this purpose, the reflector comprises two narrow, axially symmetrical sectors forming the main mirror surface regions which effect the sharp light/dark delimitation. Two parabolic additional mirror surfaces supplement these surfaces. Thus, the known reflector consists of four individual surfaces adjoining at four boundary edges. Such boundary edges cause the reflected light to form irregular light beams directed at the surface to be illuminated, so that a continuous, i.e. smooth, light distribution of high intensity is impossible.

A reflector known from DE-OS 33 41 773 shows a similar structure. Also in this case, the object of distributing the light rays reflected by the reflector in their entirety below the light/dark delimitation, is attained incompletely and discontinuously. The known reflector also consists of two parabolic sectors which are arranged symmetrically around its horizontal axis and to which adjoin two pairs of so-called deflecting surfaces. Instead of four surfaces known from the reflector according to DE-AS 18 02 113, the reflector of DE-OS 33 41 773 comprises six surfaces which adjoin at six boundary edges and which, however, do not substantially improve the disadvantages of discontinuity of light distribution, even though the adjoining boundary edges of the individual reflector surfaces allegedly do not show discontinuities.

The article "Computer Design of Automotive Lamps With Faceted Reflectors", Donohue and Joseph, J. of I.E.S./1972, pp. 36-42 describes an automotive lamp in which the reflector is divided into segments (facets) in such a manner that the reflector alone produces the pattern and lens fluting is eliminated. The many facets, as shown in FIG. 12 of that article, have sharp edges and discontinuities between them. Since each facet is a paraboloidal surface, the intersections, or junctions between the surfaces necessarily are not smooth.

U.S. Pat. No. 4,495,552 discloses a reflector for a vehicle lamp, which consists of a plurality of grid sections. Each of the grid sections shows generally a concave shape both in horizontal and in vertical cross section.

It is the object of the invention to provide a headlight that illuminates a surface to be illuminated with a desired light distribution by optimal utilization of the light source of the headlight, particularly under the consideration of the legal regulations in several countries.

The above object is attained by a method for producing an optically effective arrangement comprising one reflective surface, said arrangement having a light source related to an optical axis which extends in alignment with the optical arrangement for distributing light of said light source reflected by said reflective surface according to a desired light pattern, said method is characterized by the steps of

formulating an initial mathematical representation of at least a region of an approximated surface of said reflective surface,

mathematically manipulating of said initial representation until the resulting mathematical surface representation achieves the desired optical properties,

deriving from the resulting mathematical representation computer input data in computer input format, and

inputting said data to a computer for controlling an apparatus by which the mathematical representation of said optical surface is reproduced in physical form.

The physical form can be a vehicular headlight produced by the above-mentioned method comprising

an optically effective arrangement having one reflective surface,

a light source related to an optical axis which extends in alignment with the optically effective arrangement. This vehicular headlight is characterized in that said reflective surface shows axial asymmetry over its entire axial length, said surface having a mathematically continuous shape such that the beam of light reflected by said reflective surface distributes the light of said light source according to the distribution of the light pattern desired by optimally utilizing the light emitted by the light source.

The optically effective arrangement may be represented by the reflector surface itself.

The optically effective arrangement may also be represented by the surface of an optical element arranged in the path of the light beam reflected by the reflector surface.

The optically effective arrangement may also be a combination of the reflector surface and a surface of the optical element in the path of the light beam reflected by the reflector surface.

The surface or surfaces of the optically effective arrangement according to the invention satisfy the following single mathematical formula: ##EQU1## and wherein X represents a linear cylindrical coordinate of the headlight axis, which extends substantially in the direction of the light beam produced by the optically effective surface,

rho is the radius vector of said cylindrical coordinates,

phi represents the polar angle of said cylindrical coordinates of the loci,

n represents integers from 0 through 50, preferably through 10,

m, i and k represents integers from 0 through at least 3, preferably through 20,

R(phi) represents a coefficient which depends on phi and defines the limit value of the radii of curvature of the conic part of the surface at the apex with axial planes extending through the headlight axis when X=0,

K(phi) represents a conic section coefficient as a function of phi,

AK_(n) (phi) represents one of ne+1 different aspheric coefficients as a function of phi,

Rc_(m) and Rs_(m) each represent one of me+1, and

Kc_(i) and Ks_(i) each represent one of ie+1 different constant parameters,

AKc_(nk) and AKs_(nk) each represent one of (ne+1).(ke+1) different constant parameters.

The above optical surface formula is a variation of a known formula for a surface of rotation having coefficients R, K, AKn which are independent of phi. In this known formula, each value of X produces a certain value of rho which is thus independent of phi. Due to the dependency of the above coefficients on phi in this representation, each value of X produces a value of rho which is dependent on phi. Thus, the radius vector rho is not only a function of X, as is the case in the known formula, but also a function of phi. The designations for K and AKn as "conic section coefficients" and "aspheric coefficients", respectively, result from the known formula which contains the coefficients independent of phi. In connection with the known surfaces of rotation, the designation "basic radius" for R is also commonly used.

The optically effective system of a headlight according to the above formula can be calculated in that for me and ie, preferably 20, values of each of the parameters Rc_(m), Rs_(m), Kc_(i) and Ks_(i) and for (ne+1).(ke+1) values of the parameters AKc_(nk) and AKs_(nk), wherein preferably ne=10 and ke+20, the radius of curvature coefficient R(phi), the conic section coefficient K(phi), and the aspheric coefficients AK_(n) (phi) are determined.

Because of the mutual dependency of the coefficients in the foregoing optical surface formula, mathematical manipulation of the representation of one particular region of the surface representation causes changes in other regions of the representation, which makes the overall mathematical process of arriving at desired surface representation very complex and time-consuming. Accordingly, a preferred method according to the invention for mathematically producing the desired optical surface includes the step of mathematically representing an approximation of that surface with mathematically represented surface segments in a manner that allows individual segments to be mathematically manipulated without influencing the optical properties of other regions of the representation. Preferably, such a manner of mathematical representation uses bivariate tensor product splines. Such splines, in turn, are represented and subsequently altered, preferably either by the so-called Bezier method or by the so-called B-spline method, starting with the determination of initial bivariate polynomials which describe surface segments and are equal at the common sides of adjacent surface segments through the second derivative (continuity at the common sides of the segments).

This can be realized by the determination of initial bivariate polynomials which describe surface segments of an approximate surface to a known optical surface, e.g. a paraboloid.

In a preferred realization of this method initial bivariate polynomials are determined describing initial surface segments having desired optical properties only of an initial region of the optically effective surface. Subsequent further bivariate polynomials are determined describing further initial surface segments located adjacent to the initial region until an approximate surface to the desired optically effective surface is achieved.

In both of said realizations, said approximate surfaces are, step by step, locally changed by varying the coefficients of the bivariate polynomials while retaining said continuity through the second derivatives without influencing optical properties of other regions of said approximate surface until the resulting representation of said optical surface achieves the desired optical properties.

Regardless of the method used to devise the mathematical representation of the desired optical surface in accordance with the invention, the resulting representation is then expressed in computer language and is used as the input to a computer that controls a machine tool to reproduce the mathematical surface representation in physical form.

Due to the asymmetry of the plurality of sections intersecting the reflector and/or the optical element, each reflective spot of the reflector illuminates a definite area on the surface to be illuminated, but a region of the illuminated surface may be illuminated from more than one reflector spot, i.e., the shape of the reflector has been calculated and determined such that the light rays reflected by the reflective spots of the reflector distribute the available amount of light on the surface to be illuminated according to the brightness desired at the various spots so that an undesired brightness increase or decrease is avoided and optimal utilization of the available light source is achieved.

Consequently, light losses caused when the light beam is formed by means of the optically effective surface according to the invention are minimal, and the amount of light emitted by the light source can be fully utilized.

In addition, an improved lateral field illumination as well as a gradual, instead of an abrupt, light/dark delimination is achieved, which is desired with respect to road traffic safety. Furthermore, it is not necessary to dissipate heat developed at a masking element due to direct and indirect irradiation.

Generally, a reflective filter layer can be used expediently for heat removal from the reflector, particularly a reflector made of plastic material.

Similarly, a lens or other optical element in the light path from the reflector can be protected by a reflective filter layer on the reflector itself and/or by a cold mirror, preferably arranged at an inclined angle in front of the reflector opening. If, for example, such a cold mirror is arranged in front of the reflector at an angle of 45 degrees, the optical axis of the light beam reflected by the mirror surface will extend normal to the axis of the reflector so that an L-shaped configuration of the headlight is obtained, which fact considerably reduces the space required for installing such a system, such reduction is advantageous in an automobile. The optical means interposed in the light beam reflected by the cold mirror surface is then transilluminated only by the cold light and, as a result, can be manufactured of thermosensitive material. In this case, the axis of the headlight forms a right angle, the legs of which are the reflector axis and the optical axis of the optical element arranged in front of the reflector.

Because the headlight according to the invention does not require any of the usual diffusion screens, the automobile body designer is substantially free in shaping the headlight front glass.

A lens arranged in front of the reflector opening can either consist of a colored material or can be provided with a color filter coating to meet local requirements for coloring the light emitted by the reflector.

Surprisingly, tests conducted have shown that the optically effective surface according to the invention produces not only an optimal low beam light, but also creates an excellent high beam when using a double-filament lamp, especially because the high beam is not impaired by a masking element.

In summary, a headlight designed according to the invention avoids the use of masking elements and provides optimal utilization of the available light, achieves the desired light distribution with a considerable increase in total light output, and avoids the occurrence of color fringes.

Two embodiments of a headlight and the methods according to the invention will now be described with reference to the drawing and the accompanying tables.

FIG. 1 shows a perspective view of a first embodiment of a headlight consisting of a reflector and a lens,

FIG. 2 is a schematic perspective view of a cross-section (normal to the headlight axis) of the optically effective surface of a headlight within the coordinate system, X, Y and Z, showing cylindrical coordinates X, rho and phi, for the illustration of the first and second embodiments.

FIGS. 3a, 3b are a schematic representation of two of many possible examples for the illumination of a surface to be illuminated which can be achieved when using the headlight according to the invention,

FIG. 4 is a projection, parallel to the headlight axis "X", onto a plane normal to the X axis, of the optically effective surface of the headlight divided up into surface segments,

FIG. 5 shows an enlarged representation of one surface segment according to FIG. 4, and

FIG. 6 shows the optical path of the light rays between the optically effective surface according to FIG. 1 and a surface to be illuminated.

Table I shows the parameters for calculating the reflector surface by means of the above-mentioned formula,

Table II shows the parameters for calculating the surfaces of a lens arranged in front of the reflector which lens, together with the reflector surface, forms the optically effective system of a first embodiment of the headlight, by means of the abovementioned formula,

Tables III and IV show the coefficients (b) of the bivariate polynomials for defining the surface segments of the optically effective surface formed of the reflector surface and a lens surface according to the first embodiment.

Table V shows the "b" coefficients of the Basis-Spline-Method for defining the optically effective surface of the second embodiment of the headlight.

As shown in FIG. 1, the optically effective surface of the headlight according to a first embodiment of the invention is designed asymmetrically on a reflector 1. A lens 2 is arranged coaxially to the headlight axis 4. Reference numeral 3 designates a light source arranged within the reflector (e.g., a double filament lamp). The arrangement of the above-mentioned components on the headlight axis 4 represents one of several possible embodiments.

In addition to the surface of reflector 1, it is possible to form at least one surface of lens 2 such that one surface is characterized by point asymmetry in all planes cutting said surface, which is a part of the optically effective surface.

Moreover, lens 2 may be arranged in an offset and/or tilted relation to the headlight axis 4 to effect light emission in one or several directions other than the main direction of emission.

The glass or plastic lens 2 itself can also be used for sealing the front of the headlight. In this case, a separate front glass having an optically effective surface pattern is not required. For this purpose, at least the outer surface of the lens is scratch-resistant. Instead of the lens being used as a headlight component, a planar plate can be inserted, e.g. in the second embodiment.

For an intense light emission a double-filament lamp is provided as light source 3 so that the headlight can be used in the low and high beam mode.

The reflector surface and/or the optically effective lens surface can be described by means of the formula given in the introduction to the description.

The 12×21=252 parameters Rc_(m), Rs_(m), Kc_(i), Ks_(i), AKc_(nk) and AKs_(nk) of a reflector surface satisfying the metioned formula are given in Table I. Together with a lens which is placed in front of the reflector and the two surfaces of which are defined by the parameters given in Table II, the reflector surface forms the optically effective surface of a first embodiment of the headlight according to the invention.

The addition of E-02 or E+02 at the end of the numerical values given in Tables I and II means that such values must be multiplied by 10⁻² or 10⁺² respectively.

The values given in Table II indicate that the first lens surface has an infinitely large radius of curvature and thus represents a plane. As the second lens surface is defined only by the parameter values for me=ie=ke=0, said surface represents a surface of rotation about the headlight axis.

Using the above-described embodiment of a headlight an illumination of the surface to be illuminated will be achieved as stated in FIG. 3b in a schematically simplified form.

An initial surface used in performing the first step of a first method is based on an optically effective surface of a known shape, e.g., a paraboloid of revolution. By calculation, the initial surface is divided up into 100 initial surface segments 5' (FIG. 6), the projections of which, indicated on a plane arranged normal to the headlight axis X, are designated with the reference numeral 5 (FIGS. 4 and 5). For the purpose of simplification, the projections 5 are represented by only 25 surface segments 5' (FIG. 4).

Such sub-division results from the fact that the initial surface is dissected by means of two families of parallel planes, the planes of one of the families extending normal to the planes of the other family and the planes of both families extending parallel to the headlight axis.

With the initial surface segments 5' having thus been calculated, the corners can now be determined. In FIGS. 4 and 6, the Cartesian coordinates X, Y and Z of the headlight are represented, the X-axis defining the headlight axis. The X-coordinates of the corners b₀₀, b₀₃, b₃₀ and b₃₃ of each surface segment 5' are inserted in the following bivariate polynomial as corner coefficients: ##EQU2## wherein "y" and "z" (FIG. 5) in contrast to "X" and "Z" (FIG. 4), are Cartesian coordinates starting from corners 6 (FIG. 5) of each surface segment having the "X" coordinate "b₀₀ ".

If the Bezier method is used, the remaining coefficients of the bivariate polynomials of each surface segment, are then calculated according to this method such that the polynomials are identical in the lines of contact of adjacent surface segments through the second derivatives. The Bezier method is disclosed, for example, in W. Boehm, Gose, Einfuehrung in die Methoden der Numerischen Mathematik, Vieweg Verlag, Braunschweig, 1977, Pages 108-119. The bivariate polynomials thus calculated result in surface segments which are approximations to the initial surface segments. If then the corner coefficients of the polynomials of surface segments are varied at desired loci of the optically effective surface and subsequently, as described above, the remaining coefficients are calculated, a local change of the shape of the surface described by the polynomials will be possible, without changing other regions of that surface.

In order to obtain an optically effective surface having the desired properties, the corner coefficients of the polynomials and subsequently the remaining coefficients are step by step changed such that the desired light distribution is achieved, which can be checked each time a change has been made. This procedure is continued until the resulting mathematical surface representation achieves the desired optical properties.

The larger the number of the surface segments 5', the more the desired light distribution on the surface to be illuminated is achieved. The same applies to the degree of the bivariate polynomials, that's to say the higher the degree of the polynomials, the more the desired light distribution on the surface to be illuminated is achieved.

Proceeding from corner 6, each projection 5 of a surface segment 5' extends in "y" and "z" directions by the standardized unit of 0 to 1. In the embodiment, this unit is characterized by a polynomial having sixteen b coefficients (b₀₀ through b₃₃). For each surface segment the values for "y" and "z" are inserted in the polynomial and the coordinate "X" is calculated. The projections 5 of the surface segments 5' may be square or rectangular. The corners 6 of adjacent surface segments must, however, coincide in order to obtain the desired continuity at the contacting lines of adjacent surface segments and thus a continuity of the total reflector surface.

FIG. 5 shows an enlarged representation of a projection 5 of a surface segment 5' of the surface of reflector 1. Part of the surface segment 5' directs a light beam to the surface 7 to be illuminated (FIG. 6). In this connection, the shape of the projected image is defined by the part of the surface segment 5' forming a curve in the Y and Z directions. Depending on the required shape of the surface 7 to be illuminated, the individual adjacent surface segments are oriented such that each surface segment 5' corresponds to an area 8 on surface 7. If desired, areas 8 of different surface segments 5' may overlap or even coincide. The distribution of the amount of light on the surface 7 to be illuminated is not limited to uniformly distributing light across the total surface but, if desired, the light intensity may vary continuously across the surface to be illuminated.

In Tables III, Pages 1 through 20, and IV the "b" coefficients of the surface segments of the first embodiment of a headlight are given, said segments being described by the above-mentioned formula of bivariate polynomials. The surface segments are designated "Segments RS" in the above tables, with R and S representing the lines and columns, respectively, shown in FIG. 4.

The surface segments given in Table III form the reflector surface and the values given in Table IV define the two surfaces of a lens which is arranged in front of the reflector and, together with the reflector surface, forms the optically effective surface of the headlight effecting the illumination of the surface to be illuminated given approximately in FIG. 3b.

As will be apparent from Table IV, in this embodiment, too, the first lens surface is a plane. It follows from the values b=0 that for all loci of all surface segments, X will always be 0.

A headlight in compliance with the values given in Tables I and II or III and IV is designed such that the distance between the planar surface of lens 2 which is arranged coaxially to the axis of reflector 1 and the apex of the reflector amounts to 118 millimeters.

The preferred method for representing and manipulating the coefficients of the bivariate polynominals of the segments representing an optically effective surface for the headlight uses the Basis-spline Method according to De Boor (see "A PRACTICAL GUIDE TO SPLINES", Applied Mathematical Sciences, Volume 27, Springer Verlag Berlin, Heidelberg, N.Y.

According to this method, as in the previously described method, first bivariate polynomials are determined describing initial surface segments having desired optical properties of a region of the optically effective surface and beginning with this initial region, further bivariate polynomials are determined located adjacent to said region, until an approximate surface to said optical surface is achieved.

The achieved approximate surface is then changed locally by varying coefficients of said Basis splines while retaining continuity through the second derivatives within the varied region, without influencing optical properties of other regions of said approximate surface. Continuing in this manner the approximate surface is varied until the resulting representation of said optical surface achieves desired optical properties.

In this B-spline method for representing the optical surface, the X-range of 0 to 67 mm and phi-range of 0 to 360 degrees are divided into sub-intervals by means of partition points. Knot sequences for said ranges and sub-intervals are chosen so that fourth order B-splines in the respective variables are continuous through the second derivative. The B-splines in the X variable satisfy "not-a-know" end conditions. The B-splines in the phi variable satisfy periodic end conditions. Within the range of the variables, division points and knot sequences the resulting B-spline sequences will be denoted by B_(k) (x), K=1 to 15, and P_(j) (phi), j=1 to 15. Said reflector surface is then represented by means of the expression ##EQU3## where rho is the radius of said reflector surface at position x along the cylindrical coordinate (X-axis) axis and at angle phi with respect to the z-axis.

The Table V shows the coefficients [b_(kj) ] and knot sequences for the x variable and phi variable of a second embodiment. These data are sufficient input data for a computer to calculate a reflector surface having the desired properties when a light source lamp of known characteristics is used, e.g., a halogen H4 lamp. Referring to FIG. 2, said light source should be positioned so that the axis of its low beam filament is coincident with the x-axis with the end of the filament closest to the base located at x=29 mm. Said lamp should be oriented so that its reference pin is at angle 75° as measured from the x-axis according to the diagram in FIG. 2. The H4 lamp has three pins to orient the lamp in a housing, one of them being the reference pin.

The data indicated in the Tables I to V are generated by a computer, for instance of the type Micro-Vax 2000 using the FORTRAN language. In a subsequent step these data, representing a net of X, Y and Z coordinates, are transferred to a CAD (Computer Aided Design) Anvil program as generated by the Manufacturing Consulting System Company, U.S.A. By this program the data are converted such that a numerically controlled machine of the Fidia Company, Turin, is controlled. Eventually, the numerically controlled machine controls a milling machine of the Bohner and Koehle Company in Esslingen, Germany, for producing a reflector for a vehicular headlight according to the invention such as by forming a mold by which an optical surface of a vehicular headlight can be replicated.

                  TABLE I                                                          ______________________________________                                         Reflector surface formula parameters for the first embodiment                  ______________________________________                                         Reflector Surface                                                              m        RC.sub.m      RS.sub.m                                                ______________________________________                                          0        0.301025616E+02                                                                              0.000000000E+00                                         1       -0.776138504E+00                                                                              0.320000048E+01                                         2        0.133370183E+01                                                                              0.130136414E+01                                         3        0.215025141E+00                                                                              0.869100269E+00                                         4        0.268470260E+00                                                                              0.200731876E+00                                         5        0.184987154E+00                                                                              0.351886168E-01                                         6        0.129671173E+00                                                                             -0.403600103E-01                                         7        0.637230940E-01                                                                              0.320512819E-02                                         8        0.657042305E-01                                                                             -0.106397102E-01                                         9        0.423533490E-01                                                                             -0.160708906E-01                                        10        0.335088888E-01                                                                             -0.192834327E-01                                        11        0.137164324E-01                                                                             -0.874839426E-02                                        12        0.139906237E-01                                                                             -0.376991649E-02                                        13        0.732057473E-02                                                                             -0.646410508E-02                                        14        0.422798314E-02                                                                             -0.420884650E-02                                        15       -0.408471796E-05                                                                             -0.212006914E-02                                        16       -0.704443620E-04                                                                              0.516378266E-03                                        17       -0.860155419E-04                                                                             -0.110971614E-02                                        18       -0.110987691E-02                                                                             -0.342223479E-03                                        19       -0.897140376E-03                                                                              0.107453809E-03                                        20       -0.131258234E-02                                                                              0.000000000E+00                                        ______________________________________                                         i        KC.sub.i      KS.sub.i                                                ______________________________________                                          0       -0.429484813E+00                                                                              0.000000000E+00                                         1       -0.163727284E-01                                                                              0.337263117E-01                                         2       -0.198936600E-01                                                                             -0.608890656E-02                                         3       -0.308477079E-01                                                                              0.338959596E-01                                         4       -0.141336284E-01                                                                             -0.271903061E-02                                         5       -0.167193963E-01                                                                              0.727648203E-03                                         6       -0.595014034E-02                                                                             -0.238452148E-03                                         7       -0.601753028E-02                                                                              0.677091093E-05                                         8       -0.324424750E-02                                                                             -0.259145831E-03                                         9       -0.339949576E-02                                                                             -0.629192629E-03                                        10       -0.153724151E-02                                                                              0.366436132E-04                                        11       -0.113067112E-02                                                                             -0.259073714E-03                                        12       -0.665049967E-03                                                                             -0.114321751E-04                                        13       -0.521768369E-03                                                                             -0.175471175E-03                                        14       -0.176222083E-03                                                                              0.411897732E-04                                        15       -0.167376998E-04                                                                             -0.221832787E-04                                        16        0.666650797E-06                                                                              0.468744564E-05                                        17       -0.647191699E-05                                                                             -0.125775018E-04                                        18        0.572639607E-04                                                                              0.108406081E-04                                        19        0.325077313E-04                                                                              0.152450517E-04                                        20        0.541442594E-04                                                                              0.000000000E+00                                        ______________________________________                                         Parameters AKC.sub.nk and AKS.sub.nk                                           k        AKC.sub.4k    AKS.sub.4k                                              ______________________________________                                          0        0.231351989E-06                                                                              0.000000000E+00                                         1        0.428899918E-06                                                                             -0.108098732E-06                                         2       -0.760933804E-06                                                                             -0.171556708E-06                                         3       -0.139034183E-06                                                                             -0.114824840E-06                                         4       -0.139181386E-06                                                                             -0.900163969E-08                                         5       -0.113484337E-06                                                                             -0.113165928E-07                                         6       -0.692201245E-07                                                                              0.958364387E-08                                         7       -0.388947559E-07                                                                             -0.430786403E-08                                         8       -0.350219486E-07                                                                              0.439361829E-08                                         9       -0.254912711E-07                                                                              0.126138438E-09                                        10       -0.181330145E-07                                                                              0.301827822E-08                                        11       -0.818303372E-08                                                                              0.367433193E-09                                        12       -0.757240546E-08                                                                              0.721395733E-09                                        13       -0.434684382E-08                                                                              0.626818371E-09                                        14       -0.232837908E-08                                                                              0.302391591E-09                                        15        0.757435359E-11                                                                              0.282154895E-09                                        16        0.501081833E-10                                                                             -0.165543715E-09                                        17        0.278723188E-10                                                                              0.185979282E-09                                        18        0.615322577E-09                                                                             -0.568771854E-10                                        19        0.499060558E-09                                                                              0.672723983E-11                                        20        0.747285538E-09                                                                              0.000000000E+00                                        ______________________________________                                         k        AKC.sub.6k    AKS.sub.6k                                              ______________________________________                                          0        0.389873399E-09                                                                              0.000000000E+00                                         1       -0.517405133E-09                                                                              0.116609985E-09                                         2       -0.987346505E-10                                                                             -0.333227667E-09                                         3        0.961538761E-10                                                                              0.683053625E-10                                         4        0.199160759E-09                                                                             -0.683418244E-10                                         5        0.757325818E-10                                                                              0.331761612E-11                                         6        0.618804033E-10                                                                              0.635190239E-11                                         7        0.236550982E-10                                                                              0.810501473E-12                                         8        0.311269008E-10                                                                             - 0.263245260E-12                                        9        0.153069516E-10                                                                             -0.918383261E-12                                        10        0.111863867E-10                                                                              0.436905887E-11                                        11        0.429446358E-11                                                                             - 0.472278719E-12                                       12        0.451515603E-11                                                                              0.616508050E-12                                        13        0.244626543E-11                                                                             -0.394652800E-12                                        14        0.715797983E-12                                                                              0.123305623E-11                                        15       -0.109601896E-12                                                                             -0.108762629E-12                                        16        0.197247490E-12                                                                             -0.975652160E-13                                        17        0.946855192E-13                                                                             -0.643161886E-13                                        18       -0.479375138E-13                                                                              0.162114621E-12                                        19       -0.169187338E-12                                                                              0.154258155E-13                                        20        0.253073865E-12                                                                              0.000000000E+00                                        ______________________________________                                         k        AKC.sub.8k    AKS.sub.8k                                              ______________________________________                                          0       -0.237072296E-12                                                                              0.000000000E+00                                         1       -0.400715346E-12                                                                              0.822888353E-13                                         2        0.279627689E-12                                                                             -0.184683304E-12                                         3       -0.163001548E-12                                                                             -0.161179791E-12                                         4       -0.160168487E-12                                                                             -0.438313897E-13                                         5       -0.796791834E-13                                                                              0.661726193E-14                                         6       -0.462152595E-13                                                                              0.208456218E-14                                         7       -0.309828591E-13                                                                              0.434925264E-14                                         8       -0.241252882E-13                                                                             -0.117592616E-14                                         9       -0.168868959E-13                                                                              0.492526452E-14                                        10       -0.805788603E-14                                                                              0.224656989E-14                                        11       -0.616096672E-14                                                                              0.152796660E-14                                        12       -0.332907991E-14                                                                              0.249806639E-15                                        13       -0.262701330E-14                                                                              0.625937910E-15                                        14       -0.385394236E-15                                                                              0.758992617E-15                                        15       -0.193135632E-15                                                                             -0.234130584E-15                                        16       -0.171484070E-15                                                                             -0.278481862E-16                                        17        0.382610016E-16                                                                             -0.148401907E-15                                        18        0.308505036E-16                                                                              0.121764340E-15                                        19        0.208687007E-15                                                                             -0.154399611E-15                                        20       -0.266729468E-15                                                                              0.000000000E+00                                        ______________________________________                                         k        AKC.sub.10k   AKS.sub.10k                                             ______________________________________                                          0        0.713321483E-16                                                                              0.000000000E+00                                         1        0.533706811E-15                                                                             -0.234348896E-15                                         2        0.164872968E-15                                                                             -0.272667708E-16                                         3        0.687919021E-16                                                                             -0.134748556E-15                                         4       -0.162835300E-17                                                                             -0.117704199E-17                                         5        0.246731742E-16                                                                             -0.230461320E-17                                         6        0.667927093E-17                                                                              0.158436254E-17                                         7        0.126072927E-16                                                                              0.456377162E-18                                         8        0.409966370E-17                                                                              0.742187412E-18                                         9        0.626217680E-17                                                                              0.277419772E-17                                        10        0.311769925E-17                                                                              0.487166504E-18                                        11        0.297046067E-17                                                                              0.117760624E-17                                        12        0.141248674E-17                                                                              0.118570563E-18                                        13        0.103907576E-17                                                                              0.763942076E-18                                        14        0.544805755E-18                                                                              0.448408484E-19                                        15        0.206840560E-18                                                                              0.115951610E-18                                        16       -0.632872999E-19                                                                             -0.274282156E-19                                        17       -0.108099972E-18                                                                              0.584383839E-19                                        18       -0.214743921E-18                                                                             - 0.103994833E-19                                       19       -0.149633902E-18                                                                             -0.583100804E-19                                        20       -0.305316901E-18                                                                              0.000000000E+00                                        ______________________________________                                    

                  TABLE II                                                         ______________________________________                                         Lens surface formula parameters for the first embodiment                       ______________________________________                                         First lens surface                                                             m        RC.sub.m      RS.sub.m                                                0         0.999999999E+35                                                                             0.000000000E+00                                         ______________________________________                                         Second lens surface                                                            m        RC.sub.m      RS.sub.m                                                0        -0.270000000E+02                                                                             0.000000000E+00                                         i        KC.sub.i      KS.sub.i                                                0        -0.160000000E+01                                                                             0.000000000E+00                                         k        AKC.sub.4k    AKS.sub.4k                                              0         0.160000000E-05                                                                             0.000000000E+00                                         k        AKC.sub.6k    AKS.sub.6k                                              0        -0.910000000E-08                                                                             0.000000000E+00                                         k        AKC.sub.8k    AKS.sub.8k                                              0         0.250000000E-11                                                                             0.000000000E+00                                         ______________________________________                                          Note:                                                                          Rotational symmetry is indicated if only the value shown in the top row o      a coefficient column (Table 1) is other than zero, with values in all          other rows being zero.                                                   

                  TABLE III                                                        ______________________________________                                         Coefficients of the bivariate polynomials according to                         the Bezier method for the first embodiment                                     REFLECTOR SURFACE                                                                     s                                                                       r        3       2         1       0                                           ______________________________________                                         Segments(R,S) R 1 S 1                                                          b(s,r), wherein (s,r) are the                                                  indices of "b" according to FIG. 5                                             3        0.000   0.000     33.948  30.885                                      2        0.000   0.000     29.463  26.400                                      1        32.780  28.998    25.686  23.628                                      0        29.429  25.648    23.280  21.222                                      Segments(R,S) R 1 S 2                                                          b(s,r)                                                                         3        30.885  27.822    25.895  24.273                                      2        26.400  23.337    22.535  20.913                                      1        23.628  21.570    19.706  18.348                                      0        21.222  19.164    17.543  16.184                                      Segments(R,S) R 1 S 3                                                          b(s,r)                                                                         3        24.273  22.651    21.432  20.484                                      2        20.913  19.291    18.359  17.411                                      1        18.348  16.990    15.806  14.961                                      0        16.184  14.826    13.745  12.899                                      Segments(R,S) R 1 S 4                                                          b(s,r)                                                                         3        20.484  19.537    18.871  18.454                                      2        17.411  16.463    15.891  15.473                                      1        14.961  14.115    13.461  13.072                                      0        12.899  12.053    11.445  11.056                                      Segments(R,S) R 1 S 5                                                          b(s,r)                                                                         3        18.454  18.037    17.869  17.939                                      2        15.473  15.056    14.885  14.954                                      1        13.072  12.683    12.513  12.548                                      0        11.056  10.667    10.498  10.533                                      Segments(R,S) R 1 S 6                                                          b(s,r)                                                                         3        17.939  18.008    18.325  18.929                                      2        14.954  15.024    15.241  15.845                                      1        12.548  12.584    12.884  13.367                                      0        10.533  10.568    10.813  11.297                                      Segments(R,S) R 1 S 7                                                          b(s,r)                                                                         3        18.929  19.534    20.422  21.674                                      2        15.845  16.449    17.102  18.353                                      1        13.367  13.851    14.703  15.714                                      0        11.297  11.780    12.501  13.512                                      Segments(R,S) R 1 S 8                                                          b(s,r)                                                                         3        21.674  22.926    24.531  26.682                                      2        18.353  19.605    20.727  22.879                                      1        15.714  16.726    18.267  19.958                                      0        13.512  14.523    15.822  17.513                                      Segments(R,S) R 1 S 9                                                          b(s,r)                                                                         3        26.682  28.834    31.382  35.462                                      2        22.879  25.031    26.047  30.127                                      1        19.958  21.648    24.163  26.856                                      0        17.513  19.203    21.274  23.967                                      Segments(R,S) R 1 S 10                                                         b(s,r)                                                                         3        35.462  39.543    0.000   0.000                                       2        30.127  34.208    0.000   0.000                                       1        26.856  29.549    33.989  39.038                                      0        23.967  26.660    29.743  34.793                                      Segments(R,S) R 2 S 1                                                          b(s,r)                                                                         3        29.429  25.648    23.280  21.222                                      2        26.079  22.298    20.874  18.816                                      1        23.915  21.136    18.775  16.958                                      0        22.144  19.364    17.257  15.440                                      Segments(R,S) R 2 S 2                                                          b(s,r)                                                                         3        21.222  19.164    17.543  16.184                                      2        18.816  16.758    15.379  14.020                                      1        16.958  15.140    13.546  12.290                                      0        15.440  13.622    12.126  10.869                                      Segments(R,S) R 2 S 3                                                          b(s,r)                                                                         3        16.184  14.826    13.745  12.899                                      2        14.020  12.662    11.683  10.837                                      1        12.290  11.033    9.968   9.176                                       0        10.869  9.613     8.602   7.810                                       Segments(R,S) R 2 S 4                                                          b(s,r)                                                                         3        12.899  12.053    11.445  11.056                                      2        10.837  9.991     9.429   9.040                                       1        9.176   8.385     7.784   7.416                                       0        7.810   7.019     6.448   6.080                                       Segments(R,S) R 2 S 5                                                          b(s,r)                                                                         3        11.056  10.667    10.498  10.533                                      2        9.040   8.651     8.482   8.517                                       1        7.416   7.047     6.878   6.897                                       0        6.080   5.711     5.546   5.564                                       Segments(R,S) R 2 S 6                                                          b(s,r)                                                                         3        10.533  10.568    10.813  11.297                                      2        8.517   8.552     8.742   9.226                                       1        6.897   6.915     7.150   7.567                                       0        5.564   5.583     5.789   6.205                                       Segments(R,S) R 2 S 7                                                          b(s,r)                                                                         3        11.297  11.780    12.501  13.512                                      2        9.226   9.709     10.299  11.310                                      1        7.567   7.983     8.682   9.555                                       0        6.205   6.622     7.248   8.121                                       Segments(R,S) R 2 S 8                                                          b(s,r)                                                                         3        13.512  14.523    15.822  17.513                                      2        11.310  12.321    13.377  15.068                                      1        9.555   10.428    11.689  13.132                                      0        8.121   8.994     10.113  11.556                                      Segments(R,S) R 2 S 9                                                          b(s,r)                                                                         3        17.513  19.203    21.274  23.967                                      2        15.068  16.758    18.386  21.079                                      1        13.132  14.575    16.590  18.836                                      0        11.556  12.999    14.763  17.008                                      Segments(R,S) R 2 S 10                                                         b(s,r)                                                                         3        23.967  26.660    29.743  34.793                                      2        21.079  23.772    25.498  30.547                                      1        18.836  21.082    24.247  27.825                                      0        17.008  19.254    21.952  25.529                                      Segments(R,S) R 3 S 1                                                          b(s,r)                                                                         3        22.144  19.364    17.257  15.440                                      2        20.372  17.592    15.739  13.922                                      1        19.129  16.647    14.486  12.755                                      0        18.096  15.615    13.602  11.871                                      Segments(R,S) R 3 S 2                                                          b(s,r)                                                                         3        15.440   13.622   12.126  10.869                                      2        13.922  12.104    10.705  9.449                                       1        12.755  11.025    9.550   8.342                                       0        11.871  10.140    8.700   7.491                                       Segments(R,S) R 3 S 3                                                          b(s,r)                                                                         3        10.869  9.613     8.602   7.810                                       2        9.449   8.192     7.236   6.445                                       1        8.342   7.133     6.138   5.376                                       0        7.491   6.283     5.310   4.548                                       Segments(R,S) R 3 S 4                                                          b(s,r)                                                                         3        7.810   7.019     6.448   6.080                                       2        6.445   5.653     5.112   4.743                                       1        5.376   4.614     4.053   3.696                                       0        4.548   3.786     3.236   2.880                                       Segments(R,S) R 3 S 5                                                          b(s,r)                                                                         3        6.080   5.711     5.546   5.564                                       2        4.743   4.375     4.213   4.232                                       1        3.696   3.340     3.178   3.188                                       0        2.880   2.523     2.362   2.372                                       Segments(R,S) R 3 S 6                                                          b(s,r)                                                                         3        5.564   5.583     5.789   6.205                                       2        4.232   4.250     4.427   4.844                                       1        3.188   3.198     3.399   3.781                                       0        2.372   2.382     2.569   2.951                                       Segments(R,S) R 3 S 7                                                          b(s,r)                                                                         3        6.205   6.622     7.248   8.121                                       2        4.844   5.261     5.814   6.687                                       1        3.781   4.164     4.776   5.574                                       0        2.951   3.334     3.911   4.709                                       Segments(R,S) R 3 S 8                                                          b(s,r)                                                                         3        8.121   8.994     10.113  11.556                                      2        6.687   7.560     8.536   9.979                                       1        5.574   6.372     7.464   8.765                                       0        4.709   5.508     6.526   7.826                                       Segments(R,S) R 3 S 9                                                          b(s,r)                                                                         3        11.556  12.999    14.763  17.008                                      2        9.979   11.422    12.935  15.181                                      1        8.765   10.065    11.786  13.781                                      0        7.826   9.127     10.707  12.702                                      Segments(R,S) R 3 S 10                                                         b(s,r)                                                                         3        17.008  19.254    21.952  25.529                                      2        15.181  17.427    19.657  23.234                                      1        13.781  15.776    18.424  21.515                                      0        12.702  14.697    17.097  20.187                                      Segments(R,S) R 4 S 1                                                          b(s,r)                                                                         3        18.096  15.615    13.602  11.871                                      2        17.064  14.583    12.718  10.987                                      1        16.246  13.917    11.986  10.333                                      0        15.779  13.450    11.553  9.900                                       Segments(R,S) R 4 S 2                                                          b(s,r)                                                                         3        11.871  10.140    8.700   7.491                                       2        10.987  9.256     7.850   6.641                                       1        10.333  8.680     7.247   6.067                                       0        9.900   8.247     6.852   5.672                                       Segments(R,S) R 4 S 3                                                          b(s,r)                                                                         3        7.491   6.283     5.310   4.548                                       2        6.641   5.433     4.481   3.720                                       1        6.067   4.887     3.891   3.131                                       0        5.672   4.491     3.524   2.764                                       Segments(R,S) R 4 S 4                                                          b(s,r)                                                                         3        4.548   3.786     3.236   2.880                                       2        3.720   2.958     2.419   2.063                                       1        3.131   2.371     1.835   1.477                                       0        2.764   2.004     1.453   1.095                                       Segments(R,S) R 4 S 5                                                          b(s,r)                                                                         3        2.880   2.523     2.362   2.372                                       2        2.063   1.706     1.546   1.556                                       1        1.477   1.119     0.964   0.969                                       0        1.095   0.737     0.575   0.579                                       Segments(R,S) R 4 S 6                                                          b(s,r)                                                                         3        2.372   2.382     2.569   2.951                                       2        1.556   1.566     1.739   2.121                                       1        0.969   0.973     1.155   1.525                                       0        0.579   0.584     0.762   1.131                                       Segments(R,S) R 4 S 7                                                          b(s,r)                                                                         3        2.951   3.334     3.911   4.709                                       2        2.121   2.504     3.046   3.844                                       1        1.525   1.894     2.461   3.228                                       0        1.131   1.501     2.059   2.826                                       Segments(R,S) R 4 S 8                                                          b(s,r)                                                                         3        4.709   5.508     6.526   7.826                                       2        3.844   4.643     5.587   6.887                                       1        3.228   3.995     4.992   6.225                                       0        2.826   3.593     4.566   5.799                                       Segments(R,S) R 4 S 9                                                          b(s,r)                                                                         3        7.826   9.127     10.707  12.702                                      2        6.887   8.188     9.628   11.623                                      1        6.225   7.457     8.003   10.867                                      0        5.799   7.031     8.520   10.384                                      Segments(R,S) R 4 S 10                                                         b(s,r)                                                                         3        12.702  14.697    17.097  20.187                                      2        11.623  13.618    15.769  18.860                                      1        10.867  12.732    15.078  17.933                                      0        10.384  12.249    14.483  17.338                                      Segments(R,S) R 5 S 1                                                          b(s,r)                                                                         3        15.779  13.450    11.553  9.900                                       2        15.312  12.983    11.120  9.467                                       1        15.179  12.753    10.975  9.284                                       0        15.609  13.184    11.235  9.545                                       Segments(R,S) R 5 S 2                                                          b(s,r)                                                                         3        9.900   8.247     6.852   5.672                                       2        9.467   7.814     6.457   5.277                                       1        9.284   7.594     6.271   5.074                                       0        9.545   7.854     6.438   5.241                                       Segments(R,S) R 5 S 3                                                          b(s,r)                                                                         3        5.672   4.491     3.524   2.764                                       2        5.277   4.096     3.157   2.396                                       1        5.074   3.877     2.967   2.194                                       0        5.241   4.043     3.069   2.295                                       Segments(R,S) R 5 S 4                                                          b(s,r)                                                                         3        2.764   2.004     1.453   1.095                                       2        2.396   1.636     1.072   0.714                                       1        2.194   1.420     0.901   0.521                                       0        2.295   1.522     0.950   0.569                                       Segments(R,S) R 5 S 5                                                          b(s,r)                                                                         3        1.095   0.737     0.575   0.579                                       2        0.714   0.356     0.186   0.190                                       1        0.521   0.141     0.000   0.000                                       0        0.569   0.189     0.000   0.000                                       Segments(R,S) R 5 S 6                                                          b(s,r)                                                                         3        0.579   0.584     0.762   1.131                                       2        0.190   0.195     0.368   0.738                                       1        0.000   0.000     0.169   0.544                                       0        0.000   0.000     0.186   0.561                                       Segments(R,S) R 5 S 7                                                          b(s,r)                                                                         3        1.131   1.501     2.059   2.826                                       2        0.738   1.108     1.657   2.424                                       1        0.544   0.919     1.466   2.235                                       0        0.561   0.936     1.500   2.269                                       Segments(R,S) R 5 S 8                                                          b(s,r)                                                                         3        2.826   3.593     4.566   5.799                                       2        2.424   3.191     4.140   5.372                                       1        2.235   3.004     3.960   5.182                                       0        2.269   3.038     4.010   5.232                                       Segments(R,S) R 5 S 9                                                          b(s,r)                                                                         3        5.799   7.031     8.520   10.384                                      2        5.372   6.605     8.037   9.901                                       1        5.182   6.404     7.864   9.691                                       0        5.232   6.454     7.923   9.751                                       Segments(R,S) R 5 S 10                                                         b(s,r)                                                                         3        10.384  12.249    14.483  17.338                                      2        9.901   11.766    13.888  16.743                                      1        9.691   11.519    13.702  16.479                                      0        9.751   11.578    13.758  16.536                                      Segments(R,S) R 6 S 1                                                          b(s,r)                                                                         3        15.609  13.184    11.235  9.545                                       2        16.039  13.614    11.495  9.805                                       1        17.160  14.241    12.556  10.614                                      0        19.011  16.092    13.832  11.890                                      Segments(R,S) R 6 S 2                                                          b(s,r)                                                                         3        9.545   7.854     6.438   5.241                                       2        9.805   8.114     6.604   5.407                                       1        10.614  8.672     7.411   6.049                                       0        11.890  9.948     8.346   6.984                                       Segments(R,S) R 6 S 3                                                          b(s,r)                                                                         3        5.241   4.043     3.069   2.295                                       2        5.407   4.210     3.170   2.396                                       1        6.049   4.686     3.835   2.919                                       0        6.984   5.621     4.496   3.580                                       Segments(R,S) R 6 S 4                                                          b(s,r)                                                                         3        2.295   1.522     0.950   0.569                                       2        2.396   1.623     0.998   0.617                                       1        2.919   2.003     1.453   0.962                                       0        2.580   2.664     1.964   1.473                                       Segments(R,S) R 6 S 5                                                          b(s,r)                                                                         3        0.569   0.189     0.000   0.000                                       2        0.617   0.237     0.000   0.000                                       1        0.962   0.470     0.239   0.223                                       0        1.473   0.981     0.698   0.683                                       Segments(R,S) R 6 S 6                                                          b(s,r)                                                                         3        0.000   0.000     0.186   0.561                                       2        0.000   0.000     0.203   0.578                                       1        0.223   0.208     0.407   0.796                                       0        0.683   0.668     0.859   1.248                                       Segments(R,S) R 6 S 7                                                          b(s,r)                                                                         3        0.561   0.936     1.500   2.269                                       2        0.578   0.953     1.534   2.303                                       1        0.796   1.186     1.757   2.552                                       0        1.248   1.638     2.223   3.019                                       Segments(R,S) R 6 S 8                                                          b(s,r)                                                                         3        2.269   3.038     4.010   5.232                                       2        2.303   3.072     4.060   5.282                                       1        2.552   3.348     4.310   5.563                                       0        3.019   3.815     4.818   6.071                                       Segments(R,S) R 6 S 9                                                          b(s,r)                                                                         3        5.232   6.454     7.923   9.751                                       2        5.282   6.504     7.982   9.810                                       1        5.563   6.815     8.258   10.119                                      0        6.071   7.324     8.824   10.684                                      Segments(R,S) R 6 S 10                                                         b(s,r)                                                                         3        9.751   11.578    13.758  16.536                                      2        9.810   11.638    13.815  16.592                                      1        10.119  11.980    14.108  16.934                                      0        10.684  12.545    14.758  17.584                                      Segments(R,S) R 7 S 1                                                          b(s,r)                                                                         3        19.011  16.092    13.832  11.890                                      2        20.862  17.942    15.107  13.165                                      1        23.449  19.053    17.471  14.851                                      0        27.095  22.699    19.555  16.935                                      Segments(R,S) R 7 S 2                                                          b(s,r)                                                                         3        11.890   9.948    8.346   6.984                                       2        13.165  11.223    9.281   7.919                                       1        14.851  12.230    10.770  9.041                                       0        16.935  14.315    12.256  10.527                                      Segments(R,S) R 7 S 3                                                          b(s,r)                                                                         3        6.984   5.621     4.496   3.580                                       2        7.919   6.556     5.157   4.241                                       1        9.041   7.312     6.233   5.115                                       0        10.527  8.798     7.411   6.294                                       Segments(R,S) R 7 S 4                                                          b(s,r)                                                                         3        3.580   2.664     1.964   1.473                                       2        4.241   3.325     2.475   1.983                                       1        5.115   3.998     3.303   2.720                                       0        6.294   5.176     4.331   3.748                                       Segments(R,S) R 7 S 5                                                          b(s,r)                                                                         3        1.473   0.981     0.698   0.683                                       2        1.983   1.492     1.158   1.142                                       1        2.720   2.138     1.871   1.837                                       0        3.748   3.165     2.846   2.812                                       Segments(R,S) R 7 S 6                                                          b(s,r)                                                                         3        0.683   0.668     0.859   1.248                                       2        1.142   1.127     1.311   1.700                                       1        1.837   1.803     1.993   2.385                                       0        2.812   2.778     2.957   3.349                                       Segments(R,S) R 7 S 7                                                          b(s,r)                                                                         3        1.248   1.638     2.223   3.019                                       2        1.700   2.089     2.690   3.486                                       1        2.385   2.777     3.361   4.186                                       0        3.349   3.741     4.345   5.170                                       Segments(R,S) R 7 S 8                                                          b(s,r)                                                                         3        3.019   3.815     4.818   6.071                                       2        3.486   4.282     5.327   6.579                                       1        4.186   5.011     6.000   7.311                                       0        5.170   5.995     7.040   8.351                                       Segments(R,S) R 7 S 9                                                          b(s,r)                                                                         3        6.071   7.324     8.824   10.684                                      2        6.579   7.832     9.389   11.249                                      1        7.311   8.623     10.095  12.059                                      0        8.351   9.663     11.237  13.200                                      Segments(R,S) R 7 S 10                                                         b(s,r)                                                                         3        10.684  12.545    14.758  17.584                                      2        11.249  13.110    15.407  18.234                                      1        12.059  14.022    16.158  19.187                                      0        13.200  15.164    17.506  20.536                                      Segments(R,S) R 8 S 1                                                          b(s,r)                                                                         3        27.095  22.699    19.555  16.935                                      2        30.741  26.345    21.639  19.019                                      1        24.902  3.951     25.550  21.545                                      0        46.937  25.982    29.364  25.359                                      Segments(R,S) R 8 S 2                                                          b(s,r)                                                                         3        16.935  14.315    12.256  10.527                                      2        19.019  16.399    13.742  12.013                                      1        21.545  17.541    16.126  13.840                                      0        25.359  21.354    18.583  16.297                                      Segments(R,S) R 8 S 3                                                          b(s,r)                                                                         3        10.527  8.798     7.411   6.294                                       2        12.013  10.284    8.590   7.472                                       1        13.840  11.554    10.332  8.951                                       0        16.297  14.012    12.271  10.889                                      Segments(R,S) R 8 S 4                                                          b(s,r)                                                                         3        6.294   5.176     4.331   3.748                                       2        7.472   6.355     5.358   4.776                                       1        8.951   7.569     6.785   6.089                                       0        10.889  9.508     8.496   7.800                                       Segments(R,S) R 8 S 5                                                          b(s,r)                                                                         3        3.748   3.165     2.846   2.812                                       2        4.776   4.193     3.820   3.786                                       1        6.089   5.393     5.099   5.038                                       0        7.800   7.104     6.725   6.664                                       Segments(R,S) R 8 S 6                                                          b(s,r)                                                                         3        2.812   2.778     2.957   3.349                                       2        3.786   3.752     3.921   4.313                                       1        5.038   4.977     5.157   5.554                                       0        6.664   6.603     6.769   7.167                                       Segments(R,S) R 8 S 7                                                          b(s,r)                                                                         3        3.349   3.741     4.345   5.170                                       2        4.313   4.706     5.329   6.154                                       1        5.554   5.952     6.545   7.419                                       0        7.167   7.564     8.192   9.066                                       Segments(R,S) R 8 S 8                                                          b(s,r)                                                                         3        5.170   5.995     7.040   8.351                                       2        6.154   6.979     8.080   9.391                                       1        7.419   8.293     9.310   10.728                                      0        9.066   9.940     11.057  12.475                                      Segments(R,S) R 8 S 9                                                          b(s,r)                                                                         3        8.351   9.663     11.237  13.200                                      2        9.391   10.702    12.378  14.341                                      1        10.728  12.146    13.649  15.819                                      0        12.475  13.894    15.606  17.776                                      Segments(R,S) R 8 S 10                                                         b(s,r)                                                                         3        13.200  15.164    17.506  20.536                                      2        14.341  16.305    18.855  21.885                                      1        15.819  17.988    20.120  23.628                                      0        17.776  19.946    22.547  26.054                                      Segments(R,S) R 9 S 1                                                          b(s,r)                                                                         3        46.937  25.982    29.364  25.359                                      2        68.976  48.017    33.177  29.173                                      1        0.000   0.000     0.000   0.000                                       0        0.000   0.000     0.000   0.000                                       Segments(R,S) R 9 S 2                                                          b(s,r)                                                                         3        25.359  21.354    18.583  16.297                                      2        29.173  25.168    21.041  18.755                                      1        0.000   0.000     25.410  21.686                                      0        0.000   0.000     30.180  26.456                                      Segments(R,S) R 9 S 3                                                          b(s,r)                                                                         3        16.297  14.012    12.271  10.889                                      2        18.755  16.469    14.210  12.828                                      1        21.686  17.962    17.085  15.196                                      0        26.456  22.732    20.338  18.450                                      Segments(R,S) R 9 S 4                                                          b(s,r)                                                                         3        10.889  9.508     8.496   7.800                                       2        12.828  11.447    10.207  9.511                                       1        15.196  13.308    12.507  11.606                                      0        18.450  16.561    15.255  14.354                                      Segments(R,S) R 9 S 5                                                          b(s,r)                                                                         3        7.800   7.104     6.725   6.664                                       2        9.511   8.815     8.351   8.290                                       1        11.606  10.704    10.388  10.282                                      0        14.354  13.452    12.963  12.856                                      Segments(R,S) R 9 S 6                                                          b(s,r)                                                                         3        6.664   6.603     6.769   7.167                                       2        8.290   8.229     8.381   8.779                                       1        10.282  10.175    10.346  10.755                                      0        12.856  12.750    12.895  13.304                                      Segments(R,S) R 9 S 7                                                          b(s,r)                                                                         3        7.167   7.564     8.192   9.066                                       2        8.779   9.177     9.839   10.713                                      1        10.755  11.164    11.770  12.731                                      0        13.304  13.714    14.384  15.346                                      Segments(R,S) R 9 S 8                                                          b(s,r)                                                                         3        9.066   9.940     11.057  12.475                                      2        10.713  11.587    12.804  14.223                                      1        12.731  13.693    14.738  16.366                                      0        15.346  16.307    17.555  19.183                                      Segments(R,S) R 9 S 9                                                          b(s,r)                                                                         3        12.475  13.894    15.606  17.776                                      2        14.223  15.641    17.564  19.734                                      1        16.366  17.993    19.495  22.138                                      0        19.183  20.810    22.801  25.445                                      Segments(R,S) R 9 S 10                                                         b(s,r)                                                                         3        17.776  19.946    22.547  26.054                                      2        19.734  21.903    24.973  28.480                                      1        22.138  24.782    26.395  31.402                                      0        25.445  28.088    31.242  36.249                                      Segments(R,S) R 10 S 1                                                         b(s,r)                                                                         3        0.000   0.000     0.000   0.000                                       2        0.000   0.000     0.000   0.000                                       1        0.000   0.000     0.000   0.000                                       0        0.000   0.000     0.000   0.000                                       Segments(R,S) R 10 S 2                                                         b(s,r)                                                                         3        0.000   0.000     30.180  26.456                                      2        0.000   0.000     34.950  31.226                                      1        0.000   0.000     0.000   0.000                                       0        0.000   0.000     0.000   0.000                                       Segments(R,S) R 10 S 3                                                         b(s,r)                                                                         3        26.456  22.732    20.338  18.450                                      2        31.226  27.502    23.592  21.703                                      1        0.000   0.000     29.076  24.823                                      0        0.000   0.000     37.409  33.155                                      Segments(R,S) R 10 S 4                                                         b(s,r)                                                                         3        18.450  16.561    15.255  14.354                                      2        21.703  19.814    18.003  17.102                                      1        24.823  20.569    21.827  20.331                                      0        33.155  28.901    26.933  25.436                                      Segments(R,S) R 10 S 5                                                         b(s,r)                                                                         3        14.354  13.452    12.963  12.856                                      2        17.102  16.200    15.537  15.431                                      1        20.331  18.834    18.714  18.493                                      0        25.436  23.939    23.173  22.952                                      Segments(R,S) R 10 S 6                                                         b(s,r)                                                                         3        12.856  12.750    12.895  13.304                                      2        15.431  15.324    15.445  15.854                                      1        18.493  18.272    18.453  18.888                                      0        22.952  22.731    22.828  23.262                                      Segments(R,S) R 10 S 7                                                         b(s,r)                                                                         3        13.304  13.714    14.384  15.346                                      2        15.854  16.263    16.999  17.960                                      1        18.888  19.323    19.879  21.059                                      0        23.262  23.697    24.466  25.645                                      Segments(R,S) R 10 S 8                                                         b(s,r)                                                                         3        15.346  16.307    17.555  19.183                                      2        17.960  18.922    20.372  22.000                                      1        21.059  22.238    23.011  25.264                                      0        25.645  26.825    28.396  30.648                                      Segments(R,S) R 10 S 9                                                         b(s,r)                                                                         3        19.183  20.810    22.801  25.445                                      2        22.000  23.627    26.108  28.751                                      1        25.264  27.516    26.529  31.654                                      0        30.648  32.901    35.531  40.656                                      Segments(R,S) R 10 S 10                                                        b(s,r)                                                                         3        25.445  28.088    31.242  36.249                                      2        28.751  31.394    36.089  41.096                                      1        31.654  36.778    0.000   0.000                                       0        40.656  45.781    0.000   0.000                                       ______________________________________                                    

                  TABLE IV                                                         ______________________________________                                         Coefficients of the bivariate polynomials according to                         the Bezier method for the first embodiment                                     r      3        2           1      0                                           ______________________________________                                         FIRST LENS SURFACE                                                             Segments(R, S) R 1 S 1                                                         b(s, r), wherein (s, r) are the indices of "b" according to FIG. 5             3        0.000    0.000       0.000                                                                                 0.000                                     2        0.000    0.000       0.000                                                                                 0.000                                     1        0.000    0.000       0.000                                                                                 0.000                                     0        0.000    0.000       0.000                                                                                 0.000                                     SECOND LENS SURFACE                                                            Segments(R, S) R 1 S 1                                                         b(s, r), wherein (s, r) are the indices of "b" according to FIG. 5             3      -56.222  -51.668     -47.117                                                                               -43.157                                     2      -51.668  -47.115     -42.167                                                                               -38.207                                     1      -47.117  -42.167     -37.461                                                                               -33.853                                     0      -43.157  -38.207     -33.853                                                                               -30.245                                     Segments(R, S) R 1 S 2                                                         b(s, r)                                                                        3      -43.157  -39.197     -35.792                                                                               -32.997                                     2      -38.207  -34.247     -31.133                                                                               -28.338                                     1      -33.853  -30.245     -26.833                                                                               -24.518                                     0      -30.245  -26.637     -23.746                                                                               -21.432                                     Segments(R, S) R 1 S 3                                                         b(s, r)                                                                        3      -32.997  -30.201     -28.000                                                                               -26.300                                     2      -28.338  -25.543     -23.750                                                                               -22.050                                     1      -24.518  -22.203     -20.046                                                                               -18.707                                     0      -21.432  -19.117     -17.368                                                                               -16.030                                     Segments (R,S) R 1 S 4                                                         b(s, r)                                                                        3      -26.300  -24.600     -23.396                                                                               -22.604                                     2      -22.050  -20.350     -19.437                                                                               -18.646                                     1      -18.707  -17.368     -16.207                                                                               -15.596                                     0      -16.030  -14.691     -13.761                                                                               -13.149                                     Segments(R, S) R 1 S 5                                                         b(s, r)                                                                        3      -22.604  -21.813     -21.432                                                                               -21.432                                     2      -18.646  -17.854     -17.574                                                                               -17.574                                     1      -15.596  -14.984     -14.620                                                                               -14.620                                     0      -13.149  -12.538     -12.246                                                                               -12.246                                     Segments(R, S) R 1 S 6                                                         b(s, r)                                                                        3      -21.432  -21.432     -21.813                                                                               -22.604                                     2      -17.574  -17.574     -17.854                                                                               -18.646                                     1      -14.620  -14.620     -14.984                                                                               -15.596                                     0      -12.246  -12.246     -12.538                                                                               -13.149                                     Segments(R, S) R 1 S 7                                                         b(s, r)                                                                        3      -22.604  -23.396     -24.600                                                                               -26.300                                     2      -18.646  -19.437     -20.350                                                                               -22.050                                     1      -15.596  -16.207     -17.368                                                                               -18.707                                     0      -13.149  -13.761     -14.691                                                                               -16.030                                     Segments(R, S) R 1 S 8                                                         b(s, r)                                                                        3      -26.300  -28.000     -30.201                                                                               -32.997                                     2      -22.050  -23.750     -25.543                                                                               -28.338                                     1      -18.707  -20.046     -22.203                                                                               -24.518                                     0      -16.030  -17.368     -19.117                                                                               -21.432                                     Segments(R, S) R 1 S 9                                                         b(s, r)                                                                        3      -32.997  -35.792     -39.197                                                                               -43.157                                     2      -28.338  -31.133     -34.247                                                                               -38.207                                     1      -24.518  -26.833     -30.245                                                                               -33.853                                     0      -21.432  -23.746     -26.637                                                                               -30.245                                     Segments(R, S) R 1 S 10                                                        b(s, r)                                                                        3      -43.157  -47.117     -51.668                                                                               -56.222                                     2      -38.207  -42.167     -47.115                                                                               -51.668                                     1      -33.853  -37.461     -42.167                                                                               -47.117                                     0      -30.245  -33.853     -38.207                                                                               -43.157                                     Segments(R, S) R 2 S 1                                                         b(s, r)                                                                        3      -43.157  -38.207     -33.853                                                                               -30.245                                     2      -39.197  -34.247     -30.245                                                                               -26.637                                     1      -35.792  -31.133     -26.833                                                                               -23.746                                     0      -32.997  -28.338     -24.518                                                                               -21.432                                     Segments(R, S) R 2 S 2                                                         b(s, r)                                                                        3      -30.245  -26.637     -23.746                                                                               -21.432                                     2      -26.637  -23.029     -20.660                                                                               -18.346                                     1      -23.746  -20.660     -17.862                                                                               - 15.972                                    0      -21.432  -18.346     -15.972                                                                               -14.081                                     Segments(R, S) R 2 S 3                                                         b(s, r)                                                                        3      -21.432  -19.117     -17.368                                                                               -16.030                                     2      -18.346  -16.031     -14.691                                                                               -13.352                                     1      -15.972  -14.081     -12.413                                                                               -11.322                                     0      -14.081  -12.190     -10.777                                                                                -9.687                                     Segments(R, S) R 2 S 4                                                         b(s, r)                                                                        3      -16.030  -14.691     -13.761                                                                               -13.149                                     2      -13.352  -12.013     -11.315                                                                               -10.703                                     1      -11.322  -10.232      -9.353                                                                                -8.845                                     0       -9.687   -8.596      -7.830                                                                                -7.322                                     Segments(R, S) R 2 S 5                                                         b(s, r)                                                                        3      -13.149  -12.538     -12.246                                                                               -12.246                                     2      -10.703  -10.091      -9.871                                                                                -9.871                                     1       -8.845   -8.337      -8.062                                                                                -8.062                                     0       -7.322   -6.814      -6.567                                                                                -6.567                                     Segments(R, S) R 2 S 6                                                         b(s, r)                                                                        3      -12.246  -12.246     -12.538                                                                               -13.149                                     2       -9.871   -9.871     -10.091                                                                               -10.703                                     1       -8.062   -8.062      -8.337                                                                                -8.845                                     0       -6.567   -6.567      -6.814                                                                                -7.322                                     Segments(R, S) R 2 S 7                                                         b(s, r)                                                                        3      -13.149  -13.761     -14.691                                                                               -16.030                                     2      -10.703  -11.315     -12.013                                                                               -13.352                                     1       -8.845   -9.353     -10.232                                                                               -11.322                                     0       -7.322   -7.830      -8.596                                                                                -9.687                                     Segments(R, S) R 2 S 8                                                         b(s, r)                                                                        3      -16.030  -17.368     -19.117                                                                               -21.432                                     2      -13.352  -14.691     -16.031                                                                               -18.346                                     1      -11.322  -12.413     -14.081                                                                               -15.972                                     0       -9.687  -10.777     -12.190                                                                               -14.081                                     Segments(R, S) R 2 S 9                                                         b(s, r)                                                                        3      -21.432  -23.746     -26.637                                                                               -30.245                                     2      -18.346  -20.660     -23.029                                                                               -26.637                                     1      -15.972  -17.862     -20.660                                                                               -23.746                                     0      -14.081  -15.972     -18.346                                                                               -21.432                                     Segments(R, S) R 2 S 10                                                        b(s, r)                                                                        3      -30.245  -33.853     -38.207                                                                               -43.157                                     2      -26.637  -30.245     -34.247                                                                               -39.197                                     1      -23.746  -26.833     -31.133                                                                               -35.792                                     0      -21.432  -24.518     -28.338                                                                               -32.997                                     Segments(R, S) R 3 S 1                                                         b(s, r)                                                                        3      -32.997  -28.338     -24.518                                                                               -21.432                                     2      -30.201  -25.543     -22.203                                                                               -19.117                                     1      -28.000  -23.750     -20.046                                                                               -17.368                                     0      -26.300  -22.050     -18.707                                                                               -16.030                                     Segments(R, S) R 3 S 2                                                         b(s, r)                                                                        3      -21.432  -18.346     -15.972                                                                               -14.081                                     2      -19.117  -16.031     -14.081                                                                               -12.190                                     1      -17.368  -14.691     -12.413                                                                               -10.777                                     0      -16.030  -13.352     -11.322                                                                                -9.687                                     Segments(R, S) R 3 S 3                                                         b(s, r)                                                                        3      -14.081  -12.190     -10.777                                                                                -9.687                                     2      -12.190  -10.299      -9.141                                                                                -8.051                                     1      -10.777   -9.141      -7.788                                                                                -6.807                                     0       -9.687   -8.051      -6.807                                                                                -5.826                                     Segments(R, S) R 3 S 4                                                         b(s, r)                                                                        3       -9.687   -8.596      -7.830                                                                                -7.322                                     2       -8.051   -6.960      -6.306                                                                                -5.798                                     1       -6.807   -5.826      -5.088                                                                                -4.609                                     0       -5.826   -4.845      -4.130                                                                                -3.652                                     Segments(R, S) R 3 S 5                                                         b(s, r)                                                                        3       -7.322   -6.814      -6.567                                                                                -6.567                                     2       -5.798   -5.291      -5.072                                                                                -5.072                                     1       -4.609   -4.130      -3.892                                                                                 -3.892                                    0       -3.652   -3.173      -2.933                                                                                -2.933                                     Segments(R, S) R 3 S 6                                                         b(s, r)                                                                        3       -6.567   -6.567      -6.814                                                                                -7.322                                     2       -5.072   -5.072      -5.291                                                                                -5.798                                     1       -3.892   -3.892      -4.130                                                                                -4.609                                     0       -2.933   -2.933      -3.173                                                                                -3.652                                     Segments(R, S) R 3 S 7                                                         b(s, r)                                                                        3       -7.322   -7.830      -8.596                                                                                -9.687                                     2       -5.798   -6.306      -6.960                                                                                -8.051                                     1       -4.609   -5.088      -5.826                                                                                -6.807                                     0       -3.652   -4.130      -4.845                                                                                -5.826                                     Segments(R, S) R 3 S 8                                                         b(s, r)                                                                        3       -9.687  -10.777     -12.190                                                                               -14.081                                     2       -8.051   -9.141     -10.299                                                                               -12.190                                     1       -6.807   -7.788      -9.141                                                                               -10.777                                     0       -5.826   -6.807      -8.051                                                                                -9.687                                     Segments(R, S) R 3 S 9                                                         b(s, r)                                                                        3      -14.081  -15.972     -18.346                                                                               -21.432                                     2      -12.190  -14.081     -16.031                                                                               -19.117                                     1      -10.777  -12.413     -14.691                                                                               -17.368                                     0       -9.687  -11.322     -13.352                                                                               -16.030                                     Segments(R, S) R 3 S 10                                                        b(s, r)                                                                        3      -21.432  -24.518     -28.338                                                                               -32.997                                     2      -19.117  -22.203     -25.543                                                                               -30.201                                     1      -17.368  -20.046     -23.750                                                                               -28.000                                     0      -16.030  -18.707     -22.050                                                                               -26.300                                     Segments(R, S) R 4 S 1                                                         b(s, r)                                                                        3      -26.300  -22.050     -18.707                                                                               -16.030                                     2      -24.600  -20.350     -17.368                                                                               -14.691                                     1      -23.396  -19.437     -16.207                                                                               -13.761                                     0      -22.604  -18.646     -15.596                                                                               -13.149                                     Segments(R, S) R 4 S 2                                                         b(s, r)                                                                        3      -16.030  -13.352     -11.322                                                                                -9.687                                     2      -14.691  -12.013     -10.232                                                                                -8.596                                     1      -13.761  -11.315      -9.353                                                                                -7.830                                     0      -13.149  -10.703      -8.845                                                                                -7.322                                     Segmented (R,S) R 4 S 3                                                        b(s, r)                                                                        3       -9.687   -8.051      -6.807                                                                                -5.826                                     2       -8.596   -6.960      -5.826                                                                                -4.845                                     1       -7.830   -6.306      -5.088                                                                                -4.130                                     0       -7.322   -5.798      -4.609                                                                                -3.652                                     Segments(R, S) R 4 S 4                                                         b(s, r)                                                                        3       -5.826   -4.845      -4.130                                                                                -3.652                                     2       -4.845   -3.864      -3.173                                                                                -2.694                                     1       -4.130   -3.173      -2.461                                                                                -1.974                                     0       -3.652   -2.694      -1.974                                                                                -1.486                                     Segments(R, S) R 4 S 5                                                         b(s, r)                                                                        3       -3.652   -3.173      -2.933                                                                                -2.933                                     2       -2.694   -2.215      -1.975                                                                                -1.975                                     1       -1.974   -1.486      -1.245                                                                                -1.245                                     0       -1.486   -0.999      -0.750                                                                                -0.750                                     Segments(R, S) R 4 S 6                                                         b(s, r)                                                                        3       -2.933   -2.933      -3.173                                                                                -3.652                                     2       -1.975   -1.975      -2.215                                                                                -2.694                                     1       -1.245   -1.245      -1.486                                                                                -1.974                                     0       -0.750   -0.750      -0.999                                                                                -1.486                                     Segments(R, S) R 4 S 7                                                         b(s, r)                                                                        3       -3.652   -4.130      -4.845                                                                                -5.826                                     2       -2.694   -3.173      -3.864                                                                                -4.845                                     1       -1.974   -2.461      -3.173                                                                                -4.130                                     0       -1.486   -1.974      -2.694                                                                                -3.652                                     Segments(R, S) R 4 S 8                                                         b(s, r)                                                                        3       -5.826   -6.807      -8.051                                                                                -9.687                                     2       -4.845   -5.826      -6.960                                                                                -8.596                                     1       -4.130   -5.088      -6.306                                                                                -7.830                                     0       -3.652   -4.609      -5.798                                                                                -7.322                                     Segments(R, S) R 4 S 9                                                         b(s, r)                                                                        3       -9.687  -11.322     -13.352                                                                               -16.030                                     2       -8.596  -10.232     -12.013                                                                               -14.691                                     1       -7.830   -9.353     -11.315                                                                               -13.761                                     0       -7.322   -8.845     -10.703                                                                               -13.149                                     Segments(R, S) R 4 S 10                                                        b(s, r)                                                                        3      -16.030  -18.707     -22.050                                                                               -26.300                                     2      -14.691  -17.368     -20.350                                                                               -24.600                                     1      -13.761  -16.207     -19.437                                                                               -23.396                                     0      -13.149  -15.596     -18.646                                                                               -22.604                                     Segments(R, S) R 5 S 1                                                         b(s, r)                                                                        3      -22.604  -18.646     -15.596                                                                               -13.149                                     2      -21.813  -17.854     -14.984                                                                               -12.538                                     1      -21.432  -17.574     -14.620                                                                               -12.246                                     0      -21.432  -17.574     -14.620                                                                               -12.246                                     Segments(R, S) R 5 S 2                                                         b(s, r)                                                                        3      -13.149  -10.703      -8.845                                                                                -7.322                                     2      -12.538  -10.091      -8.337                                                                                -6.814                                     1      -12.246   -9.871      -8.062                                                                                -6.567                                     0      -12.246   -9.871      -8.062                                                                                -6.567                                     Segments(R, S) R 5 S 3                                                         b(s, r)                                                                        3       -7.322   -5.798      -4.609                                                                                -3.652                                     2       -6.814   -5.291      -4.130                                                                                -3.173                                     1       -6.567   -5.072      -3.892                                                                                -2.933                                     0       -6.567   -5.072      -3.892                                                                                -2.933                                     Segments(R, S) R 5 S 4                                                         b(s, r)                                                                        3       -3.652   -2.694      -1.974                                                                                -1.486                                     2       -3.173   -2.215      -1.486                                                                                -0.999                                     1       -2.933   -1.975      -1.245                                                                                -0.750                                     0       -2.933   -1.975      -1.245                                                                                -0.750                                     Segments(R, S) R 5 S 5                                                         b(s, r)                                                                        3       -1.486   -0.999      -0.750                                                                                -0.750                                     2       -0.999   -0.512      -0.255                                                                                -0.255                                     1       -0.750   -0.255       0.000                                                                                 0.000                                     0       -0.750   -0.255       0.000                                                                                 0.000                                     Segments(R, S) R 5 S 6                                                         b(s, r)                                                                        3       -0.750   -0.750      -0.999                                                                                -1.486                                     2       -0.255   -0.255      -0.512                                                                                -0.999                                     1        0.000    0.000      -0.255                                                                                -0.750                                     0        0.000    0.000      -0.255                                                                                -0.750                                     Segments(R, S) R 5 S 7                                                         b(s, r)                                                                        3       -1.486   -1.974      -2.694                                                                                -3.652                                     2       -0.999   -1.486      -2.215                                                                                -3.173                                     1       -0.750   -1.245      -1.975                                                                                -2.933                                     0       -0.750   -1.245      -1.975                                                                                -2.933                                     Segments(R, S) R 5 S 8                                                         b(s, r)                                                                        3       -3.652   -4.609      -5.798                                                                                -7.322                                     2       -3.173   -4.130      -5.291                                                                                -6.814                                     1       -2.933   -3.892      -5.072                                                                                -6.567                                     0       -2.933   -3.892      -5.072                                                                                -6.567                                     Segments(R, S) R 5 S 9                                                         b(s, r)                                                                        3       -7.322   -8.845     -10.703                                                                               -13.149                                     2       -6.814   -8.337     -10.091                                                                               -12.538                                     1       -6.567   -8.062      -9.871                                                                               -12.246                                     0       -6.567   -8.062      -9.871                                                                               -12.246                                     Segments(R, S) R 5 S 10                                                        b(s, r)                                                                        3      -13.149  -15.596     -18.646                                                                               -22.604                                     2      -12.538  -14.984     -17.854                                                                               -21.813                                     1      -12.246  -14.620     -17.574                                                                               -21.432                                     0      -12.246  -14.620     -17.574                                                                               -21.432                                     Segments(R, S) R 6 S 1                                                         b(s, r)                                                                        3      -21.432  -17.574     -14.620                                                                               -12.246                                     2      -21.432  -17.574     -14.620                                                                               -12.246                                     1      -21.813  -17.854     -14.984                                                                               -12.538                                     0      -22.604  -18.646     -15.596                                                                               -13.149                                     Segments(R, S) R 6 S 2                                                         b(s, r)                                                                        3      -12.246   -9.871      -8.062                                                                                -6.567                                     2      -12.246   -9.871      -8.062                                                                                -6.567                                     1      -12.538  -10.091      -8.337                                                                                -6.814                                     0      -13.149  -10.703      - 8.845                                                                               -7.322                                     Segments(R, S) R 6 S 3                                                         b(s, r)                                                                        3       -6.567   -5.072      -3.892                                                                                -2.933                                     2       -6.567   -5.072      -3.892                                                                                -2.933                                     1       -6.814   -5.291      -4.130                                                                                -3.173                                     0       -7.322   -5.798      -4.609                                                                                -3.652                                     Segments(R, S) R 6 S 4                                                         b(s, r)                                                                        3       -2.933   -1.975      -1.245                                                                                -0.750                                     2       -2.933   -1.975      -1.245                                                                                -0.750                                     1       -3.173   -2.215      -1.486                                                                                -0.999                                     0       -3.652   -2.694      -1.974                                                                                -1.486                                     Segments(R, S) R 6 S 5                                                         b(s, r)                                                                        3       -0.750   -0.255       0.000                                                                                 0.000                                     2       -0.750   -0.255       0.000                                                                                 0.000                                     1       -0.999   - 0.512     -0.255                                                                                -0.255                                     0       -1.486   -0.999      -0.750                                                                                -0.750                                     Segments(R, S) R 6 S 6                                                         b(s, r)                                                                        3        0.000    0.000      -0.255                                                                                -0.750                                     2        0.000    0.000      -0.255                                                                                -0.750                                     1       -0.255   -0.255      -0.512                                                                                -0.999                                     0       -0.750   -0.750      -0.999                                                                                -1.486                                     Segments(R, S) R 6 S 7                                                         b(s, r)                                                                        3       -0.750   -1.245      -1.975                                                                                -2.933                                     2       -0.750   -1.245      -1.975                                                                                -2.933                                     1       -0.999   -1.486      -2.215                                                                                -3.173                                     0       -1.486   -1.974      -2.694                                                                                -3.652                                     Segments(R, S) R 6 S 8                                                         b(s, r)                                                                        3       -2.933   -3.892      -5.072                                                                                -6.567                                     2       - 2.933  -3.892      -5.072                                                                                -6.567                                     1       -3.173   -4.130      -5.291                                                                                -6.814                                     0       -3.652   -4.609      -5.798                                                                                -7.322                                     Segments(R, S) R 6 S 9                                                         b(s, r)                                                                        3       -6.567   -8.062      -9.871                                                                               -12.246                                     2       -6.567   -8.062      -9.871                                                                               -12.246                                     1       -6.814   -8.337     -10.091                                                                               -12.538                                     0       -7.322   -8.845     -10.703                                                                               -13.149                                     Segments(R, S) R 6 S 10                                                        b(s, r)                                                                        3      -12.246  -14.620     -17.574                                                                               -21.432                                     2      -12.246  -14.620     -17.574                                                                               -21.432                                     1      -12.538  -14.984     -17.854                                                                               -21.813                                     0      -13.149  -15.596     -18.646                                                                               -22.604                                     Segments(R, S) R 7 S 1                                                         b(s, r)                                                                        3      -22.604  -18.646     -15.596                                                                               -13.149                                     2      -23.396  -19.437     -16.207                                                                               -13.761                                     1      -24.600  - 20.350    -17.368                                                                               -14.691                                     0      -26.300  -22.050     -18.707                                                                               -16.030                                     Segments(R, S) R 7 S 2                                                         b(s, r)                                                                        3      -13.149  -10.703      -8.845                                                                                -7.322                                     2      -13.761  -11.315      -9.353                                                                                -7.830                                     1      -14.691  -12.013     -10.322                                                                                -8.596                                     0      -16.030  -13.352     -11.322                                                                                -9.687                                     Segments(R, S) R 7 S 3                                                         b(s, r)                                                                        3       -7.322   -5.798      -4.609                                                                                -3.652                                     2       -7.830   -6.306      -5.088                                                                                -4.130                                     1       -8.596   -6.960      -5.826                                                                                -4.845                                     0       -9.687   -8.051      -6.807                                                                                -5.826                                     Segments(R, S) R 7 S 4                                                         b(s, r)                                                                        3       -3.652   -2.694      -1.974                                                                                -1.486                                     2       -4.130   -3.173      -2.461                                                                                -1.974                                     1       -4.845   - 3.864     -3.173                                                                                -2.694                                     0       -5.826   -4.845      -4.130                                                                                -3.652                                     Segments(R, S) R 7 S 5                                                         b(s, r)                                                                        3       -1.486   -0.999      -0.750                                                                                -0.750                                     2       -1.974   -1.486      -1.245                                                                                -1.245                                     1       -2.694   -2.215      -1.975                                                                                -1.975                                     0       -3.652   -3.173      -2.933                                                                                -2.933                                     Segments(R, S) R 7 S 6                                                         b(s, r)                                                                        3       -0.750   -0.750      -0.999                                                                                -1.486                                     2       -1.245   -1.245      -1.486                                                                                -1.974                                     1       -1.975   -1.975      -2.215                                                                                -2.694                                     0       -2.933   -2.933      -3.173                                                                                -3.652                                     Segments(R, S) R 7 S 7                                                         b(s, r)                                                                        3       -1.486   -1.974      -2.694                                                                                -3.652                                     2       - 1.974  -2.461      -3.173                                                                                -4.130                                     1       -2.694   -3.173      -3.864                                                                                -4.845                                     0       -3.652   -4.130      -4.845                                                                                -5.826                                     Segments(R, S) R 7 S 8                                                         b(s, r)                                                                        3       -3.652   -4.609      -5.798                                                                                -7.322                                     2       -4.130   -5.088      -6.306                                                                                -7.830                                     1       -4.845   -5.826      -6.960                                                                                -8.596                                     0       -5.826   -6.807      -8.051                                                                                -9.687                                     Segments(R, S) R 7 S 9                                                         b(s, r)                                                                        3       -7.322   -8.845     -10.703                                                                               -13.149                                     2       -7.830   -9.353     -11.315                                                                               -13.761                                     1       -8.596  -10.232     -12.013                                                                               -14.691                                     0       -9.687  -11.322     -13.352                                                                               -16.030                                     Segments(R, S) R 7 S 10                                                        b(s, r)                                                                        3      -13.149  -15.596     -18.646                                                                               -22.604                                     2      -13.761  -16.207     -19.437                                                                               -23.396                                     1      -14.691  -17.368     -20.350                                                                               -24.600                                     0      -16.030  -18.707     -22.050                                                                               -26.300                                     Segments(R, S) R 8 S 1                                                         b(s, r)                                                                        3      -26.300  -22.050     -18.707                                                                               -16.030                                     2      -28.000  -23.750     -20.046                                                                               -17.368                                     1      -30.201  -25.543     -22.203                                                                               -19.117                                     0      -32.997  -28.338     -24.518                                                                               -21.432                                     Segments(R, S) R 8 S 2                                                         b(s, r)                                                                        3      -16.030  -13.352     -11.322                                                                                -9.687                                     2      -17.368  -14.691     -12.413                                                                               -10.777                                     1      -19.117  -16.031     -14.081                                                                               -12.190                                     0      -21.432  -18.346     -15.972                                                                               -14.081                                     Segments(R, S) R 8 S 3                                                         b(s, r)                                                                        3       -9.687   -8.051      -6.807                                                                                -5.826                                     2      -10.777   -9.141      -7.788                                                                                -6.807                                     1      -12.190  -10.299      -9.141                                                                                -8.051                                     0      -14.081  -12.190     - 10.777                                                                               -9.687                                     Segments(R, S) R 8 S 4                                                         b(s, r)                                                                        3       -5.826   -4.845      -4.130                                                                                -3.652                                     2       -6.807   -5.826      -5.088                                                                                -4.609                                     1       -8.051   -6.960      -6.306                                                                                -5.798                                     0       -9.687   -8.596      -7.830                                                                                -7.322                                     Segments(R, S) R 8 S 5                                                         b(s, r)                                                                        3       -3.652   -3.173      -2.933                                                                                -2.933                                     2       -4.609   -4.130      -3.892                                                                                -3.892                                     1       -5.798   -5.291      -5.072                                                                                -5.072                                     0       -7.322   -6.814      -6.567                                                                                -6.567                                     Segments(R, S) R 8 S 6                                                         b(s, r)                                                                        3       -2.933   -2.933      -3.173                                                                                -3.652                                     2       -3.892   -3.892      -4.130                                                                                -4.609                                     1       -5.072   - 5.072     -5.291                                                                                -5.798                                     0       -6.567   -6.567      -6.814                                                                                -7.322                                     Segments(R, S) R 8 S 7                                                         b(s, r)                                                                        3       -3.652   -4.130      -4.845                                                                                -5.826                                     2       -4.609   -5.088      -5.826                                                                                -6.807                                     1       -5.798   -6.306      -6.960                                                                                -8.051                                     0       -7.322   -7.830      -8.596                                                                                -9.687                                     Segments(R, S) R 8 S 8                                                         b(s, r)                                                                        3       -5.826   -6.807      -8.051                                                                                -9.687                                     2       -6.807   -7.788      -9.141                                                                               -10.777                                     1       -8.051   -9.141     -10.299                                                                               -12.190                                     0       -9.687  -10.777     -12.190                                                                               -14.081                                     Segments(R, S) R 8 S 9                                                         b(s, r)                                                                        3       -9.687  -11.322     -13.352                                                                               -16.030                                     2      -10.777  -12.413     -14.691                                                                               -17.368                                     1      -12.190  -14.081     -16.031                                                                               -19.117                                     0      -14.081  -15.972     -18.346                                                                               -21.432                                     Segments(R, S) R 8 S 10                                                        b(s, r)                                                                        3      -16.030  -18.707     -22.050                                                                               -26.300                                     2      -17.368  -20.046     -23.750                                                                               -28.000                                     1      -19.117  -22.203     -25.543                                                                               -30.201                                     0      -21.432  -24.518     -28.338                                                                               -32.997                                     Segments(R, S) R 9 S 1                                                         b(s, r)                                                                        3      -32.997  -28.338     -24.518                                                                               -21.432                                     2      -35.792  -31.133     -26.833                                                                               -23.746                                     1      -39.197  -34.247     -30.245                                                                               -26.637                                     0      -43.157  -38.207     -33.853                                                                               -30.245                                     Segments(R, S) R 9 S 2                                                         b (s,r)                                                                        3      -21.432  -18.346     -15.972                                                                               -14.081                                     2      -23.746  -20.660     -17.862                                                                               -15.972                                     1      -26.637  -23.029     -20.660                                                                               -18.346                                     0      -30.245  -26.637     -23.746                                                                               -21.432                                     Segments(R, S) R 9 S 3                                                         b(s, r)                                                                        3      -14.081  -12.190     -10.777                                                                                -9.687                                     2      -15.972  -14.081     -12.413                                                                               -11.322                                     1      -18.346  -16.031     -14.691                                                                               -13.352                                     0      -21.432  -19.117     -17.368                                                                               -16.030                                     Segments (R, S) R 9 S 4                                                        b(s, r)                                                                        3       -9.687   -8.596      -7.830                                                                                -7.322                                     2      -11.322  -10.232      -9.353                                                                                -8.845                                     1      -13.352  -12.013     -11.315                                                                               -10.703                                     0      -16.030  -14.691     -13.761                                                                               -13.149                                     Segments(R, S) R 9 S 5                                                         b(s, r)                                                                        3       -7.322   -6.814      -6.567                                                                                -6.567                                     2       -8.845   -8.337      -8.062                                                                                -8.062                                     1      -10.703  -10.091      -9.871                                                                                -9.871                                     0      -13.149  -12.538     -12.246                                                                               -12.246                                     Segments(R, S) R 9 S 6                                                         b(s, r)                                                                        3       -6.567   -6.567      -6.814                                                                                 -7.322                                    2       -8.062   -8.062      -8.337                                                                                -8.845                                     1       -9.871   -9.871     -10.091                                                                               -10.703                                     0      -12.246  -12.246     -12.538                                                                               -13.149                                     Segments(R, S) R 9 S 7                                                         b(s, r)                                                                        3       -7.322   -7.830      -8.596                                                                                -9.687                                     2       -8.845   -9.353     -10.232                                                                               -11.322                                     1      -10.703  -11.315     -12.013                                                                               -13.352                                     0      -13.149  -13.761     -14.691                                                                               -16.030                                     Segments(R, S) R 9 S 8                                                         b(s, r)                                                                        3       -9.687  -10.777     -12.190                                                                               -14.081                                     2      -11.322  -12.413     -14.081                                                                               -15.972                                     1      -13.352  -14.691     -16.031                                                                               -18.346                                     0      -16.030  -17.368     -19.117                                                                               -21.432                                     Segments(R, S) R 9 S 9                                                         b(s, r)                                                                        3      -14.081  -15.972     -18.346                                                                               -21.432                                     2      -15.972  -17.862     -20.660                                                                               -23.746                                     1      -18.346  -20.660     -23.029                                                                               - 26.637                                    0      -21.432  -23.746     -26.637                                                                               -30.245                                     Segments(R, S) R 9 S 10                                                        b(s, r)                                                                        3      -21.432  -24.518     -28.338                                                                               -32.997                                     2      -23.746  -26.833     -31.133                                                                               -35.792                                     1      -26.637  -30.245     -34.247                                                                               -39.197                                     0      -30.245  -33.853     -38.207                                                                               -43.157                                     Segments(R, S) R 10 S 1                                                        b(s, r)                                                                        3      -43.157  -38.207     -33.853                                                                               -30.245                                     2      -47.117  -42.167     -37.461                                                                               -33.853                                     1      -51.668  -47.115     -42.167                                                                               -38.207                                     0      -56.222  -51.668     -47.117                                                                               -43.157                                     Segments(R, S) R 10 S 2                                                        b(s, r)                                                                        3      -30.245  -26.637     -23.746                                                                               -21.432                                     2      -33.853  -30.245     -26.833                                                                               -24.518                                     1      -38.207  -34.247     -31.133                                                                               -28.338                                     0      -43.157  -39.197     -35.792                                                                               -32.997                                     Segments(R, S) R 10 S 3                                                        b(s, r)                                                                        3      - 21.432 -19.117     -17.368                                                                               -16.030                                     2      -24.518  -22.203     -20.046                                                                               -18.707                                     1      -28.338  -25.543     -23.750                                                                               -22.050                                     0      -32.997  -30.201     -28.000                                                                               -26.300                                     Segments(R, S) R 10 S 4                                                        b(s, r)                                                                        3      -16.030  -14.691     -13.761                                                                               -13.149                                     2      -18.707  -17.368     -16.207                                                                               -15.596                                     1      -22.050  -20.350     -19.437                                                                               -18.646                                     0      -26.300  -24.600     -23.396                                                                               -22.604                                     Segments(R, S) R 10 S 5                                                        b(s, r)                                                                        3      -13.149  -12.538     -12.246                                                                               -12.246                                     2      -15.596  -14.984     -14.620                                                                               -14.620                                     1      -18.646  -17.854     -17.574                                                                               -17.574                                     0      -22.604  -21.813     -21.432                                                                               -21.432                                     Segments(R, S) R 10 S 6                                                        b(s, r)                                                                        3      -12.246  -12.246     -12.538                                                                               -13.149                                     2      -14.620  -14.620     -14.984                                                                               -15.596                                     1      -17.574  -17.574     -17.854                                                                               -18.646                                     0      -21.432  -21.432     -21.813                                                                               -22.604                                     Segments(R, S) R 10 S 7                                                        b(s, r)                                                                        3      -13.149  -13.761     -14.691                                                                               -16.030                                     2      -15.596  -16.207     -17.368                                                                               -18.707                                     1      -18.646  -19.437     -20.350                                                                               -22.050                                     0      -22.604  -23.396     -24.600                                                                               -26.300                                     Segments(R, S) R 10 S 8                                                        b(s, r)                                                                        3      -16.030  -17.368     -19.117                                                                               -21.432                                     2      -18.707  -20.046     -22.203                                                                               -24.518                                     1      -22.050  -23.750     -25.543                                                                               -28.338                                     0      -26.300  -28.000     -30.201                                                                               -32.997                                     Segments(R, S) R 10 S 9                                                        b(s, r)                                                                        3      -21.432  -23.746     -26.637                                                                               -30.245                                     2      -24.518  -26.833     -30.245                                                                               -33.853                                     1      -28.338  -31.133     -34.247                                                                               -38.207                                     0      -32.997  -35.792     -39.197                                                                               -43.157                                     Segments(R, S) R 10 S 10                                                       b(s, r)                                                                        3      -30.245  -33.853     -38.207                                                                               -43.157                                     2      -33.853  -37.461     -42.167                                                                               -47.117                                     1      -38.207  -42.167     -47.115                                                                               -51.668                                     0      -43.157  -47.117     -51.668                                                                               -56.222                                     ______________________________________                                     

What is claimed is:
 1. A vehicular headlight comprising:an optically effective arrangement having one reflective surface, a light source related to an optical axis which extends in alignment with the optically effective arrangement, characterized in that said reflective surface shows axial asymmetry over its entire axial length, said surface having a shape defined by a mathematical expression that is continuous and that has continuous first and second derivatives everywhere on said surface and such that the beam of light reflected by said reflective surface distributes the light of said light source according to the distribution of the light pattern desired by optimally utilizing the light emitted by the light source.
 2. A vehicular headlight comprising:an optically effective arrangement having one reflective surface, a light source related to an optical axis which extends in alignment with the optically effective arrangement, characterized in that said reflective surface shows axial asymmetry over its entire axial length such that there is no symmetry about any plane containing the axis, said surface having a mathematically continuous shape such that the beam of light reflected by said reflective surface distributes the light of said light source according to the distribution of the light pattern desired by optimally utilizing the light emitted by the light source.
 3. A vehicular headlight according to claim 1 or 2, characterized byan optical element arranged in the path of the light beam reflected by said reflective surface, said optical element having an optically effective surface which together with said reflective surface forms said optically effective arrangement.
 4. A vehicular headlight according to claim 1 or 2, characterized in that said continuous surface satisfies one single mathematical formula.
 5. A vehicular headlight according to claim 4, characterized in that the optically effective surface is designed according to the following formula: ##EQU4## and wherein X represents a linear cylindrical coordinate of the headlight axis which extends substantially in the direction of the light beam produced by the optically effective surface,rho is the radius vector of said cylindrical coordinates, phi represents the polar angle of said cylindrical coordinates of the loci, n represents integers from 0 through 50, preferably through 10, m, i and k represents integers from 0 through at least 3, preferably through
 20. R(phi) represents a coefficient which depends on phi and defines the limit value of the radii of curvature of the conic part of the surface at the apex with axial planes extending through the headlight axis when X=0, K(phi) represents a conic section coefficient as a function of phi, AK_(n) (phi) represents one of ne+1 different aspheric coefficients as functions of phi, Rc_(m) and Rs_(m) each represent one of me+1, and Kc_(i) and Ks_(i) each represent one of ie+1 different constant parameters, AKc_(nk) and AKs_(nk) each represents one of (ne+1).(ke+1) different constant parameters.
 6. A vehicular headlight according to claim 1 or 2, characterized in that said continuous surface is formulated by a mathematical representation having mathematical properties such that mathematical manipulation of local regions does not influence optical properties of other regions.
 7. A vehicular headlight according to claim 6, characterized in that said continuous surface is partitioned into quadrangular segments by intersection with two families of parallel planes, the planes of each family being parallel to said optical axis with the planes of the other of said families, said surface segments so delineated being defined by bivariate polynomials constrained so that adjacent segments are joined to form a continuous surface such that said mathematically continuous surface has at least two continuous derivatives everywhere, coefficients of said bivariate polynomials being determined by values of said polynomials at the corners of said segments and by said constraints on joining of adjacent segments. 